A method of operating an internal combustion engine, and more particularly a fuel injector is disclosed. The fuel injector is commanded to inject a fuel requested quantity. The fuel requested quantity is adjusted by closed-loop for controlling an engine speed to match a target value thereof. A value of a first parameter indicative of an amount of electrical energy supplied to an electric battery by an electric generator coupled to the internal combustion engine is measured. A value of a voltage generated by the electric battery and a value of the engine speed are measured. A reference value of the fuel requested quantity is calculated on the basis of the voltage value, the engine speed value and the value of the first parameter. A difference between the value of the adjusted fuel requested quantity and the reference value is calculated and used to control the internal combustion engine.

A method for determining an effective injection time of a valve having a coil drive includes determining an opening time of the valve, determining a closing time of the valve, and determining the effective injection time of the electric actuation of the valve for an injection operation based on the defined opening time and the defined closing time.

A method is described for operating at least one magnetic switching element, at least one first connection of at least one sensor device being connected to at least one connection of a coil of the magnetic switching element, and the first connection or an additional connection of the sensor device being connected to a reference potential, and a measuring state being established in which at least one connection of the coil is essentially at least temporarily decoupled from the reference potential and/or from a source activating the coil, and at least one signal of at least one sensor of the sensor device being ascertained in the measuring state from at least one electrical potential at at least one connection of the coil.

A fuel injection control device is adapted for a fuel injection system including an injector and a high-pressure pump that raises pressure of fuel and supplies the fuel to the injector. The fuel injection control device includes a selecting unit for selecting by which one of full lift injection and partial injection to inject fuel, and a pump control unit for controlling operation of the high-pressure pump such that a pressure of fuel supplied to the injector coincides with a target pressure. The selecting unit selects the partial injection when a required injection quantity of fuel is equal to or smaller than a partial maximum injection quantity. A fuel injection system includes the fuel injection control device, the injector, and the high-pressure pump.

Methods and systems are presented for assessing the presence or absence of engine torque deviation which may indicate air-fuel ratio imbalance between engine cylinders. In one example, the method may include assessing the presence or absence of engine torque variation based on engine torque deviation from a desired engine torque during a deceleration fuel shut-off event.

An actuator is energized to cause a valve body of a fuel injection valve to perform fuel injection. The actuator includes a driving body to drive to open and close the valve body. Boundary energization is performed that ends energization of the actuator at a timing when the driving body is moved in an opening direction of the valve body and is assumed to have reached an end of its movement range to measure a relationship between the energization time until the energization ends and the fuel injection amount. A correspondence relationship between the energization time of the actuator and the fuel injection amount is determined by using the measured relationship. An energization time corresponding to a target injection amount is obtained with reference to the determined correspondence relationship. The actuator is energized to cause the fuel injection valve to perform fuel injection.

A method for controlling the total injection mass per working cycle during a multiple injection operation of a fuel injector of an internal combustion engine is provided. In the method, an injection mass difference is determined from individual injection pulse to individual injection pulse, and transferred to the next individual injection pulse, in stepwise fashion. The injection mass difference remaining in the penultimate individual injection pulse is transferred to the final individual injection pulse to achieve a total injection mass with improved tolerance.

A system, apparatus, and method for controlling an engine system can provide fuel reactivity compensation control for an engine of the engine system. Pilot fuel quantity supplied to the engine can be controlled using a nitrous oxide (NOx) error. Likewise, air-to-fuel ratio (AFR) for the engine can be controlled using the NOx error. Each of a pilot fuel offset and an AFR control trim can be generated using the NOx error. The pilot fuel offset and the AFR control trim can be used to control the pilot fuel quantity and the AFR, respectively.

Methods and systems for calculating a plurality of aging factors in a system operating an engine. The calculated aging factors may include one or more of fuel injector drift, exhaust gas recirculation valve obstruction, and mass air flow sensor bias. Mass flow throughout the system, and pressures and temperatures within the system, are observed in an approach that relies on mass preservation concepts to estimate drift, obstruction and bias estimates.

In accordance with exemplary embodiments, methods and systems are provided for controlling fuel injection by a fuel injector of a direct injection engine. In one embodiment, a method includes: storing, in a first data storage device, a first table of values; storing, in a second data storage device, a second table of values; and adjusting, via instructions provided by a processor of the vehicle, a minimum mass value used to control the fuel injection based on an injector learned value, the first table, and the second table, wherein the injector learned value is set based on an amount of injector learning completed.